package com.chinackts.common.utils;


import org.apache.tomcat.util.codec.binary.Base64;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.nio.charset.StandardCharsets;

/**
 * @author Lianhong
 * @since 2020/5/20
 */
public class AES {

    /**
     * 加密方法
     *
     * @param data 要加密的数据
     * @param key  加密key
     * @param iv   加密iv
     * @return 加密的结果
     */
    public static String encrypt(String data, String key, String iv) {
        try {

            Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");//"算法/模式/补码方式"
            int blockSize = cipher.getBlockSize();

            byte[] dataBytes = data.getBytes();
            int plaintextLength = dataBytes.length;
            if (plaintextLength % blockSize != 0) {
                plaintextLength = plaintextLength + (blockSize - (plaintextLength % blockSize));
            }

            byte[] plaintext = new byte[plaintextLength];
            System.arraycopy(dataBytes, 0, plaintext, 0, dataBytes.length);

            SecretKeySpec keyspec = new SecretKeySpec(key.getBytes(), "AES");
            IvParameterSpec ivspec = new IvParameterSpec(iv.getBytes());

            cipher.init(Cipher.ENCRYPT_MODE, keyspec, ivspec);
            byte[] encrypted = cipher.doFinal(plaintext);
            //System.out.println("加密后："+byteToHexString(encrypted));
            return new Base64().encodeToString(encrypted);

        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    /**
     * 解密方法
     *
     * @param data 要解密的数据
     * @param key  解密key
     * @param iv   解密iv
     * @return 解密的结果
     */
    public static String desEncrypt(String data, String key, String iv) {
        try {
            byte[] encrypted1 = new Base64().decode(data);
            Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");
            SecretKeySpec keyspec = new SecretKeySpec(key.getBytes(), "AES");
            IvParameterSpec ivspec = new IvParameterSpec(iv.getBytes());
            cipher.init(Cipher.DECRYPT_MODE, keyspec, ivspec);
            byte[] original = cipher.doFinal(encrypted1);
            String originalString = new String(original, StandardCharsets.UTF_8);
            return originalString.trim();
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    /**
     * 测试
     */
    public static void main(String args[]) throws Exception {
        String key = "NEUwMDdGMDkyQzk4";
        String iv = "j0hhMZYirEyR2KSc";
        String enmi = "zWBjI01IhWWNm2vujPaMfg7c37B0dQAWJWiWZ10Vy/99cjlP7g9iVFaCJuOowgYwNydLEpR/9LFd2WQ1jqX6VVZW8PbC7OLA9YFGg9SU48k=";
        System.out.println("解密串：" + enmi);
        String dec = desEncrypt(enmi, key, iv);
        System.out.println("解密后：" + dec.replace("4bb5083d-22b3-4fe3-b474-72eafa8e2c08", ""));
    }

}
